Summary of Significant Accounting Policies - Additional Information (Details) - Accounting Standards Update 2016-09 [Member] $ in Millions	Jan. 01, 2017 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred tax asset related to excess tax benefit	$ 0.2
Deferred tax asset valuation allowance	$ 0.2

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32537-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Deferred Tax Asset
-URI http://asc.fasb.org/extlink&oid=6510090

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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